The disclosed embodiments relate to a balloon catheter to be inserted into a stenosis site inside a blood vessel for expanding the stenosis site.
Balloon catheters to be inserted into a stenosis site inside a blood vessel for expanding the stenosis site are known in the art. A typical balloon catheter includes a balloon as an expanding body, an outer shaft joined to the proximal end of the balloon, and an inner shaft inserted within the balloon and the outer shaft.
Further, it is known to provide a wire reinforcement member inside the outer shaft. This reinforcement member is intended to prevent the balloon catheter from kinking when inserted into the blood vessel and to provide improved maneuverability when an operator, such as a physician, inserts the balloon catheter into the blood vessel.
For example, Japanese Patent Application Laid-Open No. 2013-106798 (JP '798) discloses a balloon catheter with a wire member (a reinforcement member) inserted through an interior space of a middle shaft. A distal end side of the wire member is inserted through a fixing tube and a proximal end side of the wire member is fixed to a proximal end shaft.
However, there is a disadvantage in the balloon catheter of JP '798. The distal and proximal ends of the wire member (reinforcement member) are fixed with the fixing tube and the proximal end shaft, respectively. Therefore, when the balloon catheter is inserted into a curved blood vessel, the wire member (reinforcement member) cannot follow the curvature of the blood vessel smoothly and appropriately, resulting in the wire member being bent. Thus, the balloon catheter cannot be further pushed distally.
Accordingly, the disclosed embodiments provide a balloon catheter that includes a reinforcement member capable of following the curvature of a blood vessel, thus allowing for smooth passage of the balloon catheter through the curvature of the blood vessel.